Search PubMedSearch

Biomedical subjects

G Friedman

Publications and source records attributed to G Friedman.

At least 19 recordsLinked to original sources

Scavenger receptor activity and expression of apolipoprotein E mRNA in monocyte-derived macrophages of young and old healthy men.

The aim of this study was to compare some aspects of lipid metabolism in monocyte-derived macrophages isolated from young males, aged 18-24 years, and old males, aged 74-90 years, who were found healthy in accordance with the Senieur protocol. The parameters tested were metabolism of 125I-acetylated low-density lipoproteins (LDL) and oxidized LDL, incorporation of [3H]cholesterol into cholesteryl ester and expression of apolipoprotein E (apo E) mRNA. Cell association and degradation of 125I-acetylated LDL by macrophages of old and young subjects, respectively, was 15,978 +/- 2492 and 9300 +/- 1416 ng/mg cell protein per 24 h. Incorporation of [3H]cholesterol into cellular [3H]cholesteryl ester in the presence of acetylated LDL in cells isolated from old subjects was twice that in cells from young subjects. The macrophages from both age groups metabolized less 125I-oxidized LDL than 125I-acetylated LDL. Cell association and degradation of 125I-oxidized LDL in cells from old and young subjects, respectively, was 6779 +/- 1398 and 3219 +/- 643 ng/mg cell protein per 24 h. Expression of apo E mRNA was determined by reverse transcriptase polymerase chain reaction. In the basal state, it was 5.8 +/- 0.4 and 2.4 +/- 0.2 photo-stimulated luminescence (PSL) units in cells from the old and young subjects, respectively, and increased after exposure to acetylated LDL. In conclusion, these findings suggest that a combination of higher scavenger receptor activity and increased expression of apo E mRNA in macrophages could contribute to (a) enhanced metabolism of modified LDL and (b) more efficient removal of cholesterol from arteries, thus leading to healthy old age.

Acetylation

Interleukin-7-enhanced cytotoxic T lymphocyte activity after viral infection in marrow transplanted mice.

Lethally irradiated BALB/c mice were reconstituted by syngeneic bone marrow transplantation (BMT), and injected with recombinant interleukin 7 (rIL-7), recombinant interleukin 2 (rIL-2), or saline 10 days post-transplantation. Intranasal infection with A/PR8/34 influenza virus 2 weeks after BMT was associated with the highest survival rate in the rIL-7 treated group. The protective mechanism elicited by rIL-7, as manifested by very low virus titers in the lung, involves T and B cell functions. High hemagglutinin inhibition antibody levels were observed on days 7 and 12 post-challenge in the rIL-7 mice. Moreover, the anti-influenza cytotoxic T lymphocyte activity was induced primarily by rIL-7, leaving the effect of rIL-2 on the same level as that of the control. Thus, rIL-7 promotes both T cell-mediated function and B cell production during the immunodeficient state after BMT. This cytokine may prove a potential immunotherapeutic modality in BMT recipients.

Animals

Effects of nitric oxide donor SIN-1 on oxygen availability and regional blood flow during endotoxic shock.

BACKGROUND: An excessive release of nitric oxide (NO) has been incriminated in the circulatory disturbances of septic shock. OBJECTIVE: To study the effects of an NO donor, 3-morpholinosydnonimine (SIN-1), an oxygen availability and regional blood flow during endotoxic shock to see if a beneficial effect of NO synthase inhibitors in septic shock could be conclusively demonstrated. MATERIALS AND METHODS: In 14 anesthetized and mechanically ventilated dogs, global invasive hemodynamic monitoring was completed and ultrasonic flow probes were placed around the superior mesenteric, left renal, and left femoral arteries for simultaneous measurements of regional blood flow. All dogs received Escherichia coli endotoxin, 2 mg/kg. A control group (n = 7) was administered saline at 20 mL/kg per hour, and a SIN-1 group (n = 7) was given a combination of saline with SIN-1 at successive doses of 1, 2, and 4 micrograms/kg per minute. RESULTS: Neither systemic nor pulmonary arterial pressures were influenced by SIN-1. Cardiac index, stroke index, and left ventricular stroke work index did increase at low to moderate doses of SIN-1 but tended to decrease at the highest dose. Systemic and pulmonary vascular resistances decreased. Fractional blood flow increased in the mesenteric bed at all doses used, was not influenced in the renal bed, but decreased in the femoral bed at the highest dose. Oxygen-derived variables were similar in the 2 groups. Blood lactate and plasma concentrations of tumor necrosis factor were not significantly influenced. At the end of the SIN-1 infusion, the administration of 5 mg/kg of methylene blue increased arterial pressure, pulmonary arterial pressure, and systemic and pulmonary vascular resistances but decreased cardiac index and regional blood flow. CONCLUSIONS: The administration of low to moderate doses of the NO donor SIN-1 can significantly increase cardiac index and superior mesenteric blood flow without deleterious effects on arterial pressure in this model of endotoxic shock. These findings support the hypothesis that NO is essential to maintain organ blood flow even during endotoxic shock.

Animals

Facial nerve paralysis of dental origin in children.

Dental causes of facial nerve paralysis are rare and have not been previously reported in children. Two children are described with facial nerve paralysis of dental origin. The underlying mechanism of action and pathogenesis are discussed.

Adolescent

Administration of an antibody to E-selectin in patients with septic shock.

OBJECTIVES: To determine the safety and pharmacokinetics of a murine monoclonal antibody to E-selectin in patients with newly developed septic shock. DESIGN: Open-label, prospective, phase II pilot study with escalating doses of the antibody. SETTING: Intensive care unit of a 900-bed university hospital. PATIENTS: Nine patients who survived the first 24 hrs of septic shock. INTERVENTIONS: In addition to standard therapy, an intravenous bolus of a murine monoclonal antibody to E-selectin, CY1787, was given at doses of 0.1 mg/kg (n = 3), 0.33 mg/kg (n = 3), and 1.0 mg/kg (n = 3). MEASUREMENTS AND MAIN RESULTS: CY1787 was well tolerated in all patients. Signs of shock resolved in all patients, and organ failure entirely reversed in eight patients. All patients survived the 28-day follow-up. Administration of CY1787 was associated with an early and brisk increase in PaO2/FIO2 ratio (p < .001), from 146 +/- 38 mm Hg (19.5 +/- 5.1 kPa) to 205 +/- 45 mm Hg (27.3 +/- 6.0 kPa) after 2 hrs, and 250 +/- 58 mm Hg (33.3 +/- 7.7 kPa) after 12 hrs. A dose-related effect of CY1787 was suggested by an earlier weaning from catecholamine therapy and a faster resolution of organ failure in the high-dose group. Development of antimouse antibodies was documented in eight patients. CONCLUSIONS: This pilot study indicates that this antibody to E-selectin appears to be safe and may represent a promising form of therapy in septic shock.

Adult

Esophageal malignancy after liver transplantation in a patient with Barrett's esophagus.

Patients undergoing liver transplantation are predisposed to develop extrahepatic malignancies. It is also known that patients with predisposed conditions, such as Barrett's esophagus, have higher rates of esophageal carcinoma. We present here a patient who underwent liver transplantation, had Barrett's esophagus, and developed esophageal malignancy a short time after transplantation. Liver transplantation may be associated with acceleration of the precancerous condition and the development of malignancies.

Adenocarcinoma

Stimulation of immune reconstitution by interleukin-7 after syngeneic bone marrow transplantation in mice.

Successful outcome of autologous bone marrow transplantation (BMT) is severely handicapped by susceptibility to infection and by a high rate of relapse. While quantitative aspects of the immune system generally return to normal within the first 3-4 months after BMT, the recovery of qualitative immune functions is prolonged. Since interleukin-7 (IL-7) has growth-promoting and differentiating effects on pre-B cells and immature thymocytes, its role in the recovery of immune functions was investigated in BALB/c mice after syngeneic BMT (sBMT). After sBMT, mice treated with human recombinant IL-7 (rIL-7) showed an 11.9-fold increase in thymic cellularity associated with an enhanced response to a mitogenic stimulus compared with the controls. rIL-7 significantly increased RAG-1 expression and promoted V beta 8(D)J gene rearrangement of the T cell receptor in the thymus. Further, the cytokine boosted survival after challenge with influenza virus following sBMT. The finding that rIL-7 induces differentiation and proliferation of immature thymocytes and counteracts post-BMT immune deficiency makes it a promising medium for clinical application in BMT patients.

Animals

Pneumatosis cystoides intestinalis: laparoscopic features.

Pneumatosis cystoides intestinalis (PCI) is a condition characterized by the presence of gas-filled cysts in the submucosa or subserosa of the gastrointestinal tract. PCI has been described by various radiographic methods but its laparoscopic features have not been previously described. We report a case of a 77-yr-old male with marked ascites and radiographic evidence of pneumatosis cystoides intestinalis of the ileum who underwent a laparoscopy to determine the cause of his ascites. The characteristic laparoscopic features of PCI are described, and its radiographic features are reviewed.

Aged

Dehydroepiandrosterone enhances influenza immunization in aged mice.

The effect of DHEA administration on the age-associated decline in immunity against influenza vaccine was studied. Increased humoral response was observed in 16- and 24-month-old mice immunized by live A/PR/8/34 (H1N1) influenza virus following DHEA treatment (a single injection adjacent to immunization). Furthermore, DHEA-treated mice demonstrated increased resistance to postvaccination intranasal challenge with live influenza virus. Thus, DHEA treatment overcomes the age-related defect in the immunity of old mice against influenza.

Aging

Effect of transforming growth factor-beta on lipoprotein lipase in rat mesenchymal heart cell cultures.

The effect of recombinant transforming growth factor-beta 2 (rTGF-beta 2) on lipoprotein lipase (LPL) synthesis was studied in mesenchymal rat heart cell cultures. Addition of rTGF-beta 2 to culture medium containing 20% serum resulted in a time-dependent decrease in LPL activity. With 10 ng/ml a 30% fall occurred after 12 h and only 20% of enzyme activity remained after 24 h with 5 or 10 ng/ml. The minimal effective dose of rTGF-beta 2 was 0.1 ng/ml and a 20% decrease occurred after exposure for 24 h. Antibodies specific to TGF-beta 2 blocked this effect. The decrease in enzymic activity was accompanied by a decrease in enzyme mass and LPL mRNA. Addition of rTGF-beta 2 was effective only during the first week in culture, when enzyme activity was increasing but not after 12 days when the cultures were overconfluent, and the enzyme activity was high.

Animals

Clinical and biological significance of interleukin-10 plasma levels in patients with septic shock.

Interleukin-10 is a potent macrophage-deactivating cytokine that inhibits lipopolysaccharide-induced tumor necrosis factor production. We determined the plasma levels of immunoreactive interleukin-10 in 16 patients with septic shock and in 11 patients with circulatory shock of nonseptic origin. In septic shock, interleukin-10 levels peaked during the first 24 h (median: 48 pg/ml) and decreased progressively till Day 5. In nonseptic shock, interleukin-10 plasma levels also increased during the first 24 h but to a lesser extent (median: 17 pg/ml). In septic shock patients, interleukin-10 plasma levels were positively correlated with tumor necrosis factor (r = 0.8, p = 0.01) and with parameters of shock severity including lactate levels (r = 0.56, p < 0.05) and correlated negatively with blood platelet counts (r = -0.65, p < 0.05). The decreased production of tumor necrosis factor-alpha and interleukin-6 after in vitro incubation of whole blood from septic shock patients with lipopolysaccharide was not influenced by in vitro neutralization of interleukin-10. We conclude that interleukin-10 is produced in patients with circulatory shock of septic and nonseptic origin and that the production of this anti-inflammatory cytokine during septic shock correlates positively with the intensity of the inflammatory response.

Adult

European participation in major intensive care journals.

To evaluate the recent evolution of the European contribution to the international literature in intensive care medicine, we reviewed the source of all original articles and case reports published from 1989 to 1993 in 5 major journals: Critical Care Medicine, Intensive Care Medicine, Chest, The American Review of Respiratory Disease and Circulatory Shock. There was an overall decline in the US contributions and a corresponding increase in the European participations to Chest and the American Review of Respiratory Disease, but not to Critical Care Medicine or Circulatory Shock. The European participation to Intensive Care Medicine remained largely predominant. The evaluation of the contributions of major European countries to these 5 journals revealed a progressive increase in the French, Italian and Spanish contributions, whilst the German contribution remained stable and the UK contributions decreased. The UK contribution, which was the first in 1989, became second in 1993, after France.

Authorship

Dehydroepiandrosterone (DHEA) treatment reverses the impaired immune response of old mice to influenza vaccination and protects from influenza infection.

Dehydroepiandrosterone (DHEA) is a native steroid with an immunomodulating activity. Recently it was suggested that its age-associated decline is related with immunosenescence. To examine whether DHEA administration could effectively reverse the age-associated decline of immunity against influenza vaccine, aged mice were simultaneously vaccinated and treated with DHEA. Reversal of the age-associated decline and a significant constant increase of humoral response was observed in treated mice. Increased resistance to post-vaccination intranasal challenge with live influenza virus was observed in DHEA-treated aged mice. Thus, DHEA treatment overcame the age-related defect in the immunity of old mice against influenza.

Adjuvants, Immunologic

Combined measurements of blood lactate concentrations and gastric intramucosal pH in patients with severe sepsis.

OBJECTIVE: To compare the prognostic value of blood lactate concentrations, gastric intramucosal pH, and their combination in patients with severe sepsis. DESIGN: Prospective, noninterventional study. SETTING: Medical/surgical intensive care unit of a university hospital. PATIENTS: The study included 35 consecutive patients (44 to 82 yrs) with severe sepsis as defined by fever or hypothermia (rectal temperature > 38.3 degrees or < 35.5 degrees C), tachycardia (heart rate > 100 beats/min), tachypnea (respiratory rate > 20 breaths/min) or mechanical ventilation, abnormal white blood cell count (> 10 or < 6 x 10(3) cells/mm3), hypotension (systolic arterial pressure < 90 mm Hg), and evidence of organ dysfunction (oliguria or deterioration of mental status). INTERVENTIONS: Arterial lactate concentration and intramucosal pH were measured at the time of study entry, and at 4 and 24 hrs later. Hemodynamic data and oxygen-derived variables were determined at the time of study entry and 24 hrs later. Arterial blood and balloon saline gases were also determined to obtain the pH gap (arterial pH-intramucosal pH) and the PCO2 gap (intramural PCO2-PaCO2). MEASUREMENTS AND MAIN RESULTS: Of the 35 patients, 19 survived the intensive care unit stay. At the time of study admission, 23 (66%) patients had an increased lactate concentration (> 2 mEq/L) and 26 (74%) had a low intramucosal pH (< 7.32). Initially, there were no significant differences in blood lactate concentrations between nonsurvivors and survivors (3.2 +/- 1.5 vs. 2.8 +/- 2.3 mEq/L). Lactate concentrations remained high in nonsurvivors and progressively decreased in survivors (4 hrs: 3.3 +/- 1.1 mEq/L in nonsurvivors vs. 2.2 +/- 0.9 mEq/L in survivors [p < .01]; 24 hrs: 3.5 +/- 2.0 mEq/L in nonsurvivors vs. 1.9 +/- 1.1 mEq/L in survivors [p < .05]). Intramucosal pH was lower in the nonsurvivors than in the survivors initially (7.19 +/- 0.15 in nonsurvivors vs. 7.30 +/- 0.14 in survivors [p < .05]), at 4 hrs (7.18 +/- 0.17 in nonsurvivors vs. 7.29 +/- 0.13 in survivors [p = .06]), and at 24 hrs (7.19 +/- 0.31 in nonsurvivors vs. 7.30 +/- 0.17 in survivors [p < .05]). Of the 23 patients with initially high lactate concentrations, 12 (60%) of the 20 patients with low intramucosal pH died, as compared with one (33%) of the three patients with normal intramucosal pH (p = .052). Of the 14 patients with persistently high lactate concentrations at 24 hrs, all nine (100%) patients with low intramucosal pH, but only two (40%) of five patients with normal intramucosal pH died (p < .001). No significant relationship was found between lactate or intramucosal pH and oxygen-derived variables. Intramucosal pH correlated better with gastric intramural PCO2 (r2 = .58) than with arterial bicarbonate or base deficit/excess. Intramural PCO2 was a more specific predictor of mortality than intramucosal pH. When compared with patients with normal lactate concentrations, those patients with high lactate concentrations had a higher pH gap (0.22 +/- 0.22 vs. 0.07 +/- 0.13 [p < .01]) and PCO2 gap [21.0 +/- 33.9 vs. 1.8 +/- 9.8 torr [2.79 +/- 4.5 vs. 0.24 +/- 1.34 kPa]; p < .01). CONCLUSIONS: Both lactate concentrations and intramucosal pH represent reliable prognostic indicators in severe sepsis, and their combination improves the prognostic assessment in these patients. Both variables are better prognostic indicators than oxygen-derived variables. Intramural PCO2 appears to be a more specific variable than intramucosal pH, which partially reflects systemic metabolic acidosis. Combined determinations of blood lactate concentrations and intramucosal pH or intramural PCO2 may help to predict outcome from severe sepsis.

APACHE

Early hemodynamic course of septic shock.

OBJECTIVE: To assess the relative contributions of changes in vascular tone and changes in cardiac function to hemodynamic recovery from septic shock. DESIGN: Case series, observational study. SETTING: Multidisciplinary department of intensive care in an academic hospital. PATIENTS: Sixty-seven patients with septic shock (prolonged hypotension, signs of tissue hypoperfusion, signs of sepsis, suspected source of infection, or documented bacteremia). In addition to the antibiotic therapy and the removal of the source of sepsis whenever possible, each patient received intravenous fluids and vasoactive agents (dopamine, norepinephrine, and dobutamine). Each patient was also treated with mechanical ventilation. Twenty-four (36%) patients survived their intensive care unit course. INTERVENTIONS: Hemodynamic measurements were obtained at baseline, after initial resuscitation (as soon as apparent hemodynamic stability was achieved), after 12 hrs, and after 24 hrs. MEASUREMENTS AND MAIN RESULTS: There were no significant differences in hemodynamic or oxygen-derived variables at baseline between the survivors and the nonsurvivors. During the initial resuscitation period, only the survivors demonstrated a significant increase in mean arterial pressure (from 69 +/- 17 to 82 +/- 18 mm Hg; p < .02) and left ventricular stroke work index (from 25.2 +/- 11.0 to 35.5 +/- 19.4 g.m/m2; p < .05). The increases in cardiac index and systemic vascular resistance were greater in the survivors than in the non-survivors, but the differences did not reach statistical significance. Study of the left ventricular function curves indicated an improvement of left ventricular function in the survivors but not in the nonsurvivors. CONCLUSION: An early improvement in left ventricular function is a hallmark of the survivors from septic shock.

Adolescent